Chuck.



. Patented Dec. l2, I899. H. CASLEB.

\\N WN ATTORNEYS 638,905- Patented Dec. I2, 1899.

H. CASLER.

,OHUOK.

(Application in; July 13, 1698.)

2 Shuts-Sheet 2.

(No Model.)

INVENTOR WITNESSES BY c ' ATTORNEYS m: Nonms versus no mYo-utnu.wmmuufon. n. c-

amt STATES PATENT Grinch.

HERMAN CASLER, OF OANASTOTA, NEW YORK.

CHUCK.

SPECIFICATION forming part of Letters Patent No. 638,905, dated December12, 1899.

Application filed July 13, 1898. Serial No. 685,828. (No model.)

To all whom it may concern.-

Be it known that I, HERMAN OAsLER, a citizen of the United States'esiding at Oanas tota, in the county of Madison and State of New York,have invented certain new and use ful Improvements in Chucks and Idohereby declare the following to be a full, clear, and exactdescription of the invention, such as will enable others skilled in theart to which it appertains to make and use the same.

My invention relates to improvements in chucks; and it consists in thenovel means employed for holding objects placed within the chuck and forcentering the same automatically and in the novel combination,construction, and arrangement of the parts.

The objects of my invention are, first, to provide improved m ans to:holding objects placed within the chuck and for automatically centeringthe same and which shall not score, indent, or otherwise injure thesurfaces of such objects, and, second, to make the chuck simple andinexpensive in construction, compact, strong, durable, and not liable toderangement. These objects are attained in the chuck herein described,and illustrated in the drawings which accompany and form a part of thisspecification; in which the same reference-numerals indicate the same orcorresponding parts, and in which-- Figure 1 is a central longitudinalsection of the chuck. Fig. 2 is a view of the rear end thereof. Fig. 3is a side view and partial section of the chuck on the line as x ofFig. 1. Fig. 4c is a longitudinal'section of one of the linerbushin gshereinafter referred to and employed for adapting the chuck to receiveobjects having smaller diameters than any to which the gripping-bushingof the chuck may be reduced, and Fig. 5 is a detail view of the end ofthe key by which the chuck is operated.

The chuck herein illustrated and described is particularly adapted forholdin gwork which has been turned to size, and is thereforeparticularly useful in finishing work, and more so as it does not score,indent, or otherwise injure the surfaces of objects held by it.

In the drawings, 1 is the main shell or casing of the chuck.

2 is a bushing mounted in the bore of the shell 1 and movable to someextent longitudinally therein, but held against rotary motion by a key3.

dis acomparatively thin split bushing within the bushing 2.

The bushings 2 and 4C are provided with engaging teeth, which forconvenience in inserting the bushing 4 are preferably screw-teeth. Theseteeth act as wedges to contract the split bushing 4 when the bushing 2is moved. longitudinally toward the front end of the chuck, ashereinafter described, so causing the bushing 4:t0 grasp objects placedwithin it. The faces of these teeth therefore are inclined at a veryoblique angle with the axis of the chuck. The wedge-teeth terminate ashort distance from the end of the bushing 4t, and in their stead thebushing 4. is provided with screw-teeth of rectangular form adapted toresist thrust and engaging corresponding teeth in a base-plate 5. Thisbase-plate is secured to the main shell or casing 1 of the chuck byscrews 6. (Shown in Fig. 2.) A key 7 secured to the base-plate 5 andengaging the bushing 4E, prevents rotation of said bushing.

The casing 1 contains an annular chamber in front of the base-plate 5,within which is a bevel gear-wheel 8, having screw-threads engagingcorresponding screw-threads of the bushing 2. A bevel-pinion 9, alsowithin this annular chamber of the casing 1, engages the bevel-gear 8.The pinion 9 has no shaft or spindle, except as the key by which thechuck is operated forms a spindle temporarily, but is held in place,since it fits somewhat closely within the annular chamber in the casing1, and is further held in engagement with the gear 8 by a shoulder 10 ofthe casing 1.

The keyhole 11 in the center of this pinion 9 has a square or otherangular form. Opposite this keyhole 11 are round holes 12 and 13 in thewalls of the casing 1. The key 14, by which the chuck is operated andthe end of which is shown in Fig. 5, has portions 11, 12, v

and 13, correspondingin form to the form of the holes 11, 12, and 13,respectively. The portions 12' and 13 ofthe key 14: form journalstherefor when the key is inserted into the chuck, so that the key isitself the supporting pin or spindle of the pinion 9 at the times whensaid pinion is to be rotated.

The operation of the chuck is as follows:

To contract the chuck about an object placed within the bushing a, thekey 14 is inserted into the keyhole in the pinion 9 and rotated. Themotion thus imparted to the bevel-pinion 9 is communicated to thebevel-gear S. The gear 8 is held between the casing 1 and the base-plate5 and cannot move longitudiiially, and therefore its rotation forces thebushing 2 outward or toward the top of Fig. 1. The split bushing L isheld against longitudinal movement, however, by its screwthreadsengaging the base-plate 5, and therefore its sides are pressed inward bythe action of the wedge-shaped teeth of the bushing 2 against itscorresponding teeth. The contraction of the bushing 4 thus produced issufficient to cause said bushing to grasp objectsplaced Within it whichare of nearly the same diameter as the bore of the bushing whenexpanded. If the object to be held in the chuck be ofconsiderably-smaller diameter than the bore of the bushing 4, alinerbushing 15, such as is shown in Fig. 4:, may be inserted, and thechuck may be provided with a number of these liner-bushings of differentsizes, so that it may accommodate objects of different diameters. Theliner-bushings are provided with longitudinal slots, as shown, so thatthey are readily expansible and contractible.

By a reverse operation to that above described the chuck may be openedto release any object placed within it.

Because the bushing 4 is itself centered with respect to the chuck andholds objects placed within it on all sides objects which have beenturned to size are centered when held by the chuck. The same is true ofthe liner-bushings when they are employed.

Because the pressure of the bushing 4, or the liner-bushing, is exertedover so large a surface work is held firmly within the chuck without anyscoring, indenting, or other injury to the surfaces of the work.

An important advantage of this chuck is that after an object has beenclamped in it the position of such object is not altered by tighteningthe chuck, as is the case with many chucks. This is a great advantagewhen the end of an object held within the chuck is to be faced off orwhen a slot is to be cut in such object.

Having thus completely described my invention, what I claim, and desireto secure by Letters Patent, is-

1. In a chuck, the combination, with an elastic split bushing havingwedge-shaped screw-threads, of a device for varying the diameter of saidbushing, having corresponding and intermeshing wedge-shaped screwthreads coacting with the threads of the bushing, acting as wedges tocause the bushing to contract or to expand, when the said device ismoved with respect to the bushing according to the direction of motion,said screwthreaded device being provided with means whereby it may bemoved with respect to said bushing, substantially as described.

2. In a chuck, the combination, with an elastic split bushing havingWedge-shaped screw-threads the working faces of which are set at anangle of less than forty-five degrees with respect to the axis of thebushing, whereby said threads are adapted to serve as wedges, of adevice for varying the diameter of said bushing having corresponding andintermeshing wedgeshaped screw-threads which coact with the threads ofthe bushing, acting as wedges to cause the bushing to contract or toexpand, when said device is moved with respect to the bushing, accordingto the direction of motion, said screw-threaded device being providedwith means whereby it may be moved with respect to the bushing.

23. In achuck, the combination,with abushing of variable diameterprovided with wedgeshaped screw-threads engaging corresponding threadsof an object adapted to be moved longitudinally with respect to saidbushing, and thereby to vary the diameter of the bushing, of a casinginclosing said bushing of variable diameter and said object, and meanswithin and carried by the casing for imparting such longitudinalmovement to said object, substantially as described.

4. In a chuck, the combination, with two concentric bushings, onelocated within the other, and provided with engaging wedgeshapedscrew-threads, one of said bushings being of variable diameter and theother being adapted to be moved longitudinally with respect to saidbushing of variable diameter, of acasinginclosing said bushings, andmeans within and carried by the casing for produc-' ing suchlongitudinal movement,- substantially as described.

5. In a chuck, the combination, witha casing, and two bushings withinsaid casing, one located within the other, and provided with engagingwedge-shaped screw-threads, one of said bushings being of variablediameter, of means for holding one of said bushings stationary withinsaid casing, and means within and carried by the casing for producinglongitudinal movements of the other bushing with respect to thestationary bushing, substantially as described.

6. In a chuck, the combination, with a casing, and twobushings withinsaid casing, one located within the other, and provided with engagingwedge-teeth, one of said bushings being of variable diameter, of abase-plate engaging projections of one of said bushings and adapted toprevent longitudinal move= ment of said bushing, andmeans for producinglongitudinal movement of the other bushing, substantially as described.

7. In achuck,the combination, withabushing of variable diameter providedwith wedgeteeth engaging corresponding teeth of an object adapted to bemoved longitudinally with respect to said bushing, and thereby to varythe diameter of the bushing, of a ring upon said object and connectedthereto by screwteeth, means for preventing longitudinal movement ofsaid ring, and means for rotating said ring, thereby producinglongitudinal movement of said object, substantially as described.

8. In a chuck, the combination, with a casing, and two bushings withinsaid casing, one located Within the other, and provided with engagingWedge-teeth, one of said bushings being of variable diameter, of meansfor holding one of said bushings within said casing, a bevel gear-wheelwithin said casing and mounted upon and connected to the other bushingby screw-teeth, a bevel-pinion engaging said bevel-gear, means forrotating said pinion, and means for preventing longitudinal movement ,ofthe bevel-gear, whereby when said gear is rotated longitudinal movementof its bushing is produced, substantially as described.

9. In a chuck, the combination, with a casing, and two bushings withinsaid casing, one

located within the other, and provided with engaging wedge-teeth, one ofsaid bushings being of variable diameter, of means for holding one ofsaid bushings within said casing, a bevel gear-Wheel Within said casingand mounted upon and connected to the other bushing by screw-teeth,abevel-pinion engaging said bevel-gear and held in engagement therewithby a projecting shoulder of the casing, and provided with a suitablehole for the insertion of a key by which it maybe rotated, the casingbeing provided with a bearing for the key when inserted into the pinion,and means for preventing longitudinal movement of the bevel-gear,whereby when said gear is rotated longitudinal move ment of its bushingis produced, substantially as described.

In testimony whereof I affix my signature in presence of two witnesses.

HERMAN CASLER. lVitnesses:

ALBERT O. BRIGGS, G. H. Ross.

